<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        .box{
            display: flex;
            justify-content: space-around;
            width: 600px;
            height: 600px;
            border: 1px solid;
        }
        .box div {
            width: 100px;
            height: 100px;
            background-color: red;
            border: 1px solid;
        }
    </style>
</head>
<body>
<!-- flex 布局模型专门用来布局 默认为横向主轴布局 -->
<div class="box">
    <div class="zi"></div>
    <div class="zi"></div>
    <div class="zi"></div>
</div>
</body>
</html>